The Hawks (19-3) fell behind 29-23 in the third quarter, after the Buccaneers’ Daniel Fowler converted a three-point play with 7:26 seconds left on the clock.
That’s when Castlin and teammate B.J. Brown took over.
Brown and Castlin made back-to-back 3-pointers to tie the game and start a 20-3 run over a 6-minute span that put Hillgrove ahead 43-32 with 48 seconds remaining in the period.
Brown, who finished with 15 points, four rebounds and three steals, totaled seven points in the period. Combined with Castlin’s 15, the duo scored all 22 of Hillgrove’s third-quarter points as the Hawks outscored the Buccaneers (17-5) by a 22-11 margin and built a 43-37 lead entering the fourth quarter.
Fowler’s layup at the 5:30 mark of the fourth left Allatoona trailing by three, but Castlin’s jumper sparked a 14-3 spurt for Hillgrove, which pulled ahead 59-45 with 2 minutes left in the game.
Castlin, who added 13 rebounds, two assists and three steals in the contest, scored eight points during the run, capping it with a 3-pointer and a three-point play.
“He’s just Kyle,” Hillgrove coach Ed Morris said. “That’s what he does. He’s an outstanding player and a great kid on and off the floor. He made a lot of plays for us (Saturday) and helped bring a lot of energy to our team.”
Energy is what Morris felt was lacking from his team in the first half. Hillgrove trailed 13-6 in the first quarter but closed it to two points following a 3 from Brown and a jumper from Castlin.
Allatoona built a six-point advantage on Austin Faulkner’s 3-pointer with just under 2 minutes remaining in the second quarter before Hillgrove closed it to five at the break.
The Hawks were more aggressive on the rebounds in the second half and pushed the ball up the court when they could, resulting in several free-throw attempts in the third quarter.
“I talked to the guys at halftime about energy and enthusiasm,” Morris said. “We weren’t moving as well in the first half as we did in the second half. Everybody had that energy, enthusiasm and effort in the second half, which was huge for us.”
Hillgrove took a 62-47 lead with 53 seconds remaining, after Brown made the first of his two free throws. Allatoona, which totaled seven 3-pointers, found its stroke late in the game as Jacob Morrison converted a four-point play, and Mario Baggs’ 3 with 3 seconds left was the final score of the contest.
Keith Ray added eight points, three rebounds, two steals and two assists for Hillgrove.
Fowler, who had 11 in the second half, paced the Buccaneers with 15 points, 11 rebounds and three assists. Paul Bloodworth had seven points, five boards and two steals, while Baggs totaled 12 points. Morrison finished with eight.
Hillgrove 66, Allatoona 61: The Lady Hawks had four players score in double figures, and they battled back from a 10-point first-quarter deficit in the non-region game.
Mackenzie Engram totaled 19 points, including 10 in the second quarter, and was 8-for-8 from the free-throw line for the Lady Hawks. She also had seven rebounds and five blocks.
Aleigha Cass contributed 13 points, nine rebounds and three steals, while Tene Thompson had 13 points, four rebounds, five assists and two steals and was 6-for-8 from the line. Zarriah Pierce finished with 15 points, including three 3-pointers, and collected three steals.
Kennedy Thomas added six points, four rebounds, three steals and three assists for Hillgrove, which made 19 of 21 free throws in the contest.
“It was a good team effort,” Hillgrove coach Susan Milam said. “We had four kids in double figures, and we’re looking for more of that. We want more balance. It was good to see some defensive stops down the stretch, too.”
Allatoona (11-7), which saw its five-game win streak snapped, took a 21-13 first-quarter lead behind Alyssa Dobson, who scored 11 of her 20 points in the first quarter and finished with 18 first-half points.
Hillgrove trailed 30-25 with a minute and a half left when Elise Spann was called for a technical foul away from a shooting foul. Thompson made the two technical free throws, and Engram connected on both of her free throws, to move the Lady Hawks to within one.
Engram and Cass then closed the first half with back-to-back field goals to tie the contest at 33-all heading into intermission.
Jessica Finch, who scored 16 points — including seven in the fourth quarter — hit one of her three 3-pointers with 3:42 in the third to knot the contest at 42-all.
Hillgrove led 51-46 entering the fourth and opened up a 60-48 lead with 5:56 left before Allatoona stormed back on an 11-0 run and trailed 60-59 with 2:08 remaining.
Engram made a big block late in the game and the Lady Hawks went 6-for-6 from the free-throw line down the stretch to pull out the victory.
Alexis Ezell had nine points and nine rebounds for Allatoona. Spann finished with seven points and four assists, while Brianna Middleton had five points and six rebounds.